// bson_collection_catalog_entry.h

/**
 *    Copyright (C) 2014 MongoDB Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects for
 *    all of the code used other than as permitted herein. If you modify file(s)
 *    with this exception, you may extend this exception to your version of the
 *    file(s), but you are not obligated to do so. If you do not wish to do so,
 *    delete this exception statement from your version. If you delete this
 *    exception statement from all source files in the program, then also delete
 *    it in the license file.
 */

#pragma once

#include <string>
#include <vector>

#include "mongo/db/catalog/collection_catalog_entry.h"

namespace mongo {

    /**
     * This is a helper class for any storage engine that wants to store catalog information
     * as BSON. It is totally optional to use this.
     */
    class BSONCollectionCatalogEntry : public CollectionCatalogEntry {
    public:
        BSONCollectionCatalogEntry( const StringData& ns );

        virtual ~BSONCollectionCatalogEntry(){}

        virtual CollectionOptions getCollectionOptions( OperationContext* txn ) const;

        virtual int getTotalIndexCount( OperationContext* txn ) const;

        virtual int getCompletedIndexCount( OperationContext* txn ) const;

        virtual BSONObj getIndexSpec( OperationContext* txn,
                                      const StringData& idxName ) const;

        virtual void getAllIndexes( OperationContext* txn,
                                    std::vector<std::string>* names ) const;

        virtual bool isIndexMultikey( OperationContext* txn,
                                      const StringData& indexName) const;

        virtual DiskLoc getIndexHead( OperationContext* txn,
                                      const StringData& indexName ) const;

        virtual bool isIndexReady( OperationContext* txn,
                                   const StringData& indexName ) const;

        // ------ for implementors

        struct IndexMetaData {
            IndexMetaData() {}
            IndexMetaData( BSONObj s, bool r, DiskLoc h, bool m )
                : spec( s ), ready( r ), head( h ), multikey( m ) {}

            void updateTTLSetting( long long newExpireSeconds );

            std::string name() const { return spec["name"].String(); }

            BSONObj spec;
            bool ready;
            DiskLoc head;
            bool multikey;
        };

        struct MetaData {
            void parse( const BSONObj& obj );
            BSONObj toBSON() const;

            int findIndexOffset( const StringData& name ) const;

            /**
             * Removes information about an index from the MetaData. Returns true if an index
             * called name existed and was deleted, and false otherwise.
             */
            bool eraseIndex( const StringData& name );

            void rename( const StringData& toNS );

            std::string ns;
            CollectionOptions options;
            std::vector<IndexMetaData> indexes;
        };

    protected:
        virtual MetaData _getMetaData( OperationContext* txn ) const = 0;

    };

}
